Surely, the lion's share of our work as HVAC controls engineers concerns the delivery and maintenance of comfortable conditions. If a building is uncomfortable, seemingly everyone knows who we are; if it is comfortable, we maintain our relative anonymity. As a result, we tend to be comfort-obsessed. This bias negatively impacts our ability to be successful in the critical-controls marketplace, where comfort is of only secondary concern. Consider:

  • In laboratories, fume-hood face velocity, dynamic airflow balance, and space pressure impact safety. If workers are exposed to toxins, how important is it that the lab is comfortable?

  • If the Food and Drug Administration shuts down a pharmaceutical plant because batches of drugs were manufactured outside the environmental conditions specified in the product license, how important is it that the workers were comfortable?

    In addition to comfort, cost often takes a back seat where critical controls are concerned. For instance, in vivariums, where months and even years of research can be tied up in the well-being of the animals housed there, cost usually is not at the top of the owner's list of concerns in selecting a controls supplier.

    Early in my career, I discovered critical controls to be a market in which customers pay a premium, still feel they got their money's worth, and reward suppliers with repeat business. So, if you are tired of competing in the commercial marketplace, where comfort is the primary goal and price the principal value proposition, look to critical controls.

Over the years, I have seen both individuals and global controls companies fail in trying to establish a presence in the critical-controls market. Many took jobs at what they perceived to be sizable markups, only to see margins and profits erode as the projects dragged on. This has taught us that:

  • The mindset and practices that make a company successful in the realm of commercial controls are likely to make it unsuccessful in the realm of critical controls, largely because the typical controls provider has built a business delivering acceptable comfort at the lowest cost. Acceptable performance for a school is far different than that for an aseptic manufacturing facility.

  • With critical controls, the learning curve can be steep and the process of overcoming it time-consuming and expensive. While controls engineers may know hardware and software inside and out, the same cannot always be said for applications. Unfortunately, there are no seminars to attend or books to read to bone up on critical-controls applications. Most individuals who are proficient at delivering critical controls have learned their craft the hard way, through experience and mistakes.

  • Critical controls require a more structured and formalized engineering process than do commercial controls. Any commissioning agent will tell you that the average control submittal reflects what is required to get the project approved for release, not what will be installed. Sequences tend to mimic what engineers specify, not what is programmed into controllers. Design changes are made on the fly and documented with pencil marks on paper copies of submittals. Rarely is there an engineering review before modifications are implemented. As-builts often do not match installations. When comfort is the principal metric of success, how a job gets done is relatively unimportant. On a critical-controls job, however, “good-enough” engineering does not cut it, as the design, execution, and documentation need to withstand scrutiny.

  • With critical controls, every sensor, damper, and valve needs to be touched to verify proper operation and calibration. Additionally, each control loop needs to be tuned beyond the default values set during program development.

  • Each type of critical application has its own set of requirements. These may be set forth in federal regulations, as in the pharmaceutical world, or industry standards, as in the lab world.

Success in the critical-controls market is not achieved easily. However, the rewards — loyal customers, higher margins, less competition — are great.


The founder and principal of Facility Diagnostics Inc. (www.facilitydiagnostics.com), an engineering-services provider specializing in mission-sensitive ventilation systems and their controls, Ken Kolkebeck has more than 30 years of experience in the controls field.

Next month in HPAC Engineering, look for Ken Kolkebeck's feature article on building automation for pharmaceutical manufacturing.

For previous Control Freaks columns or to visit the Networked Controls “microsite,” go to www.hpac.com.